6
3.
RC250 Receiver
3.1
Packed items
•
RC250 receiver with serial and Modbus output (RS232)
•
Antenna (basic whip)
–
Eltek type UHFFlexi/SMA
•
MP12U power supply with regional adaptor
•
LC68
–
RC250 to PC serial lead
•
USB to serial converter lead
•
LCTX3
–
Transmitter to PC serial lead
•
RxConfig software
•
Optional RS485 adapter (must be ordered with RC250
–
see
accessories.)
3.2
RxConfig software
RxConfig can also be downloaded from: www.eltekdataloggers.co.uk
When installed, RxConfig creat
es a folder “Eltek”. In this folder are the RC250
documents for details of Modbus over serial, etc. for Modbus limitations.
The program allows the user to:-
•
Read transmitter settings
•
Set the transmitter interval
•
Associate an RC250 Channel with a specific transmitter channel
•
Meter configured RC250 channels
3.3
Operation
The RC250 works by first receiving a data 'packet' from a transmitter, verifying
it, then storing it to be read by the external device or PC. It is verified by means
of a checksum contained in the message and the associated transmitter
number.
If the RC250 does not receive a message from a transmitter within a
configured time, the stored value will be set to “no data”. For more detail see
“No Data interval”
on page 8 (Section 11).
Example application: Typically data from the RC250 to the PC is updated every
30 minutes, so the transmitter interval is set to 5 minutes (that this PC update
period ÷ 6) and the “No Data” interval to 2 hours. (that is PC update period x
4). If the transmitter stops transmitting for any reason the PC should register
this fact after 2 hours.
3.4
Power Requirements
The RC250 requires permanent AC mains connection. Use only the AC power
supply type MP12U provided. Built-in Ni-Mh batteries provide up to 3 days
standby in the event of power failure. A fully discharged battery is charged in
